Display device

ABSTRACT

A display device includes a housing; at least one roller positioned within the housing; a display portion including a display panel and a module cover; and an operating portion connected to one end of the display portion and to change a display portion&#39;s state, wherein the display panel and the module cover transition from a first state where the display panel and the module cover are wound around the at least one roller to a second state where the display panel and the module cover are unwound from the at least one roller, in contact with each other, and exposed out of the housing. The operating portion includes a motor assembly; a support, one end which is connected to one end of the display portion and an other end which is connected to the motor assembly; a transmission portion, one end of which is connected to the support; and an auxiliary link connected to the housing and connected to an other end of the transmission portion, the auxiliary link including a spring portion to exert force on the transmission portion.

This application claims the benefit of Korean Patent Application No.10-2015-0167361 filed on Nov. 27, 2015, and No. 10-2015-0185190 filed onDec. 23, 2015, the entire contents of which are incorporated herein byreference for all purposes as if fully set forth herein.

BACKGROUND Field of the Disclosure

The present disclosure relates to a display device, and moreparticularly, to a display device that allows for less force for a motorby using a spring portion to push a transmission portion.

Background

With the development of the information society, demand for variousdisplays is increasing. Responding to this demand, various displays suchas LCDs (liquid crystal display devices), PDPs (plasma display panels),ELDs (electroluminescent displays), VFDs (vacuum fluorescent displays),etc., are being researched and used.

Among these displays, those using organic light-emitting diodes (OLEDs)offer superior luminance and viewing angles compared to LCDs and can bemade extremely thin because they work without a backlight.

SUMMARY

One aspect is to provide a display device including a housing; at leastone roller positioned within the housing; a display portion including adisplay panel and a module cover; and an operating portion connected toone end of the display portion and to change a display portion's state,wherein the display panel and the module cover transition from a firststate where the display panel and the module cover are wound around theat least one roller to a second state where the display panel and themodule cover are unwound from the at least one roller, in contact witheach other, and exposed out of the housing, and wherein the operatingportion includes a motor assembly; a support, one end of which isconnected to one end of the display portion and an other end which isconnected to the motor assembly; a transmission portion, one end whichis connected to the support; and an auxiliary link connected to thehousing and connected to an other end of the transmission portion, theauxiliary link including a spring portion to exert force on thetransmission portion.

The spring portion may include first to third springs.

At least one of the first to third springs may have a different springconstant.

The third spring, which is the farthest of the three springs from thetransmission portion, may have the highest spring constant.

The auxiliary link may further include supporters positioned among thefirst to third springs, within the auxiliary link.

The supporters may include: a main supporter positioned between at leastone of the first to third springs and an adjacent spring; and a sidesupporter positioned at an end of at least one of the first and thirdsprings.

The display device may further include: a roller hub attached to acenter axis of the at least one roller; a constant spring spaced apartfrom the roller hub; and a transmission belt wound around the constantspring and the roller hub.

The constant spring may rotate in an opposite direction to the rollerhub during a transition from at least either the first or second stateto the other state.

The rotational force of the roller hub may be larger than the torque ofthe constant spring during a transition from the first state to thesecond state.

The roller hub may rotate in a first direction during a transition fromthe second state to the first state and rotate in a second directionduring a transition from the first state to the second state.

The module cover may include a plurality of aprons, at least some ofwhich are connected to one another.

The display device may further include a bracket positioned below the atleast one roller, with a side facing the at least one roller beingconcaved.

The diameter of the concaved portion of the bracket may be larger thanthe diameter of the at least one roller.

At least one guide bar may be positioned at an entrance where thesupport ascends from or descends into the housing.

The at least one guide bar may include first and second guide bars, thefirst and second guide bars being positioned at opposite sides of thesupport.

The operating portion may further include: a guide wheel positioned at ajoint of the transmission portion and the auxiliary link; and a guiderail positioned at the housing, into which the guide wheel is inserted.

The guide wheel may rotate and move from one end of the guide rail tothe other end during a transition from the first state to the secondstate.

The display panel and the module cover may be wound or unwound by tworollers.

The at least one roller may include: a panel roller to wind or unwindthe display panel; and an apron roller to wind or unwind the modulecover, in conjunction with the winding or unwinding of the displaypanel.

The at least one roller may include a guide roller to space the modulecover and the panel roller apart from each other.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention. In the drawings:

FIGS. 1 to 6 are views showing the configuration of a display devicerelating to an exemplary embodiment of the present invention;

FIGS. 7 to 31 are views showing a display device according to anexemplary embodiment of the present invention; and

FIGS. 32 to 43 are views showing a display device according to anotherexemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail embodiments of the inventionexamples of which are illustrated in the accompanying drawings. Sincethe present invention may be modified in various ways and may havevarious forms, specific embodiments are illustrated in the drawings andare described in detail in the present specification. However, it shouldbe understood that the present invention are not limited to specificdisclosed embodiments, but include all modifications, equivalents andsubstitutes included within the spirit and technical scope of thepresent invention.

The terms ‘first’, ‘second’, etc., may be used to describe variouscomponents, but the components are not limited by such terms. The termsare used for the purpose of distinguishing one component from othercomponents. For example, a first component may be designated as a secondcomponent without departing from the scope of the present invention. Inthe same manner, the second component may be designated as the firstcomponent.

The term “and/or” encompasses both combinations of the plurality ofrelated items disclosed and any item from among the plurality of relateditems disclosed.

When an arbitrary component is described as “being connected to” or“being linked to” another component, this should be understood to meanthat still another component(s) may exist between them, although thearbitrary component may be directly connected to, or linked to, thesecond component. In contrast, when an arbitrary component is describedas “being directly connected to” or “being directly linked to” anothercomponent, this should be understood to mean that no component existsbetween them.

The terms used in the present application are used to describe onlyspecific embodiments or examples, and are not intended to limit thepresent invention. A singular expression can include a plural expressionas long as it does not have an apparently different meaning in context.

In the present application, the terms “include” and “have” should beunderstood to be intended to designate that illustrated features,numbers, steps, operations, components, parts or combinations thereofexist and not to preclude the existence of one or more differentfeatures, numbers, steps, operations, components, parts or combinationsthereof, or the possibility of the addition thereof.

Unless otherwise specified, all of the terms which are used herein,including the technical or scientific terms, have the same meanings asthose that are generally understood by a person having ordinaryknowledge in the art to which the present disclosure pertains. The termsdefined in a generally used dictionary must be understood to havemeanings identical to those used in the context of a related art, andare not to be construed to have ideal or excessively formal meaningsunless they are obviously specified in the present application.

The following exemplary embodiments of the present invention areprovided to those skilled in the art in order to describe the presentdisclosure more completely.

Hereinafter, a display panel will be described by taking an organiclight-emitting display (OLED) as an example. However, display panelsapplicable to the present invention are not limited to OLEDs, but mayinclude liquid crystal panels (LCPs), plasma display panels (PDPs), orfield emission display panels (FED panels).

FIGS. 1 to 6 are views showing the configuration of a display devicerelating to an exemplary embodiment of the present invention.

As illustrated in FIG. 1, in what follows, a display panel 10 mayinclude a first long side LS1, a second long side LS2 facing the firstlong side LS1, a first short side SS1 adjacent to the first long sideLS1 and the second long side LS2, and a second short side SS2 facing thefirst short side SS1.

Here, the first short side SS1 may be referred to as a first side area,the second short side SS2 may be referred to as a second side areafacing the first side area, the first long side LS1 may be referred toas a third side area adjacent to the first and second side areas andpositioned between the first and second side areas, and the second longside LS2 may be referred to as a fourth side area adjacent to the firstand second side areas, positioned between the first and second sideareas, and facing the third side area.

For convenience of explanation, the first and second long sides LS1 andLS2 are longer in length than the first and second short sides SS1 andSS2; but, it should be noted that the first and second long sides LS1and LS2 may be approximately the same length as the first and secondshort sides SS1 and SS2.

In what follows, a first direction DR1 may be parallel to the long sidesLS1 and LS2 of the display panel, and a second direction DR2 may beparallel to the short sides SS1 and SS2 of the display panel 10.

A third direction DR3 may be perpendicular (or orthogonal) to the firstdirection DR1 and/or the second direction DR2.

The first direction DR1 and the second direction DR2 may be collectivelyreferred to as a horizontal direction or a vertical direction,respectively.

The third direction DR3 may be referred to as orthogonal direction.

Referring to FIG. 2, the display device 100 according to an embodimentof the present invention may include a display portion 20 and a housing30.

The display portion 20 may include a display panel 10 and a module cover15. The display panel 10 may be provided on the front of the displaydevice 100 and display an image. A controller may display an image atthe display panel 10 by breaking an image down into pixels andcontrolling the color, brightness, and intensity of light emitted byeach individual pixel at the display panel 10. The display panel 10 maybe divided into an active region where an image is displayed and aninactive region where no image is displayed.

The display panel 10 may be rectangular. However, the display panel 10is not limited to such a shape and also may be shaped to have apredetermined curvature at the corners. The display panel 10 may be anorganic light-emitting diode (OLED) panel. However, the display panel isnot limited to such a panel. For example, the display panel may be aliquid crystal display panel.

The module cover 15 may be provided behind the display panel 10. Themodule cover 15 may be attached directly to the display panel 10. Themodule cover 15 may be the same size as or larger than the display panel10.

The module cover 15 may support the back of the display panel 10.Accordingly, the module cover 15 may include a material that islightweight and high in strength. For example, the module cover 15 mayinclude aluminum.

The housing 30 may be provided on the back of the display portion 20.That is, the housing 30 may be provided on the back of the module cover15. The housing may shield at least one printed circuit board (PCB).That is, the housing 30 may cover at least one PCB attached at the backof the module cover 15. A detailed structure of the at least one PCB anda method of attaching the same will be described below.

Electronic signals from the at least one PCB may be transmitted to thehousing 30. Accordingly, the housing 30, though not shown, may becomprised of an inner housing made of conductive material and an outerhousing covering the inner housing. However, the housing 30 is notlimited to such a structure, and may be a single unit made of conductivematerial.

Referring to FIG. 3, in the display device 100 according to anembodiment of the present invention, the housing 30 may be positionedunder the display portion 20. In more detail, the housing 30 may have ashape that covers the bottom of the display portion 20. The housing 30may be configured as not to expose drive equipment or drive circuits init.

The widths of the housing 30 along the first and third directions may belarger than the width of the display portion 20, in order to protect thedisplay portion within the housing 30. The width of the housing 30 alongthe second direction may be smaller than the width of the displayportion 20, in order to prevent the housing 30 from obstructing theuser's field of vision.

In the display device 100 according to the embodiment of the presentinvention, the housing 30 may not be positioned in the active region ofthe display portion 20. Accordingly, the display portion 20 may be madethinner, allowing the user to immerse themselves in the screen.

Referring to FIG. 4, in the display device 100 according to theembodiment of the present invention, the active region of the displayportion 20 may be in a first state where the active region of thedisplay portion 20 is within the housing 30 or a second state where theactive region of the display portion 20 is exposed out of the housing30.

When the display device 100 is in the first state, the active region ofthe display portion 20 may be within the housing 30. That is, thedisplay portion 20 may be shielded in the housing 30.

When the display device 100 is in the second state, the active region ofthe display portion 20 may be exposed out of the housing 30. That is,when the display portion 20 is in the second state, part of the displayportion 20 may protrude out above the housing 30.

Although not shown in this figure, the display portion 20 may changefrom the first state to the second state by means of a roller within thehousing 30. In more detail, when the roller unrolls, the display portion20 may change from the first state in which it is wound around theroller to the second state in which the display portion 20 is unwoundfrom the roller to be exposed to the outside. In contrast, when theroller rolls back, the display portion 20 may change from the secondstate to the first state. A detailed structure of the roller and thedisplay portion 20 and a method of operating them will be describedlater.

In the display device 100 according to the embodiment of the presentinvention, the display portion 20 may be either in the first state or inthe second state. Accordingly, the user may save space by only exposingthe display portion 20 out of the housing 30 when viewing the displaydevice 100.

Referring to FIG. 5, in the display device according to the embodimentof the present invention, a panel roller 143 may be connected to oneedge of the display panel 10. The panel roller 143 may wind or unwindthe display panel 10 in order to bring the display panel 10 to eitherthe first state or the second state.

In the display device according to the embodiment present invention, atleast one source PCB 120 may be positioned on at least part of the frontsurface of the display panel 10. Each source PCB 120 may be spaced apartfrom each other.

The at least one source PCB 120 may have signal wires for transmittingdigital video data and timing control signals from a timing controllerboard 105 within the panel roller 143. The source PCB 120 may beconnected to the display panel 10 by a source chip on film (COF) 123.The source COF 123 connected to one side of the source PCB 120 mayconnect to the display panel 10 as it extends to the active region ofthe display panel 10.

A seat portion 379 may be positioned on the outer circumference of thepanel roller 143. That is, at least part of the outer circumference ofthe panel roller 143 is flat. The seat portion 379 may be positionedwhere the source PCB 120 makes contact with the panel roller 143 as thepanel roller 143 is rolled. The seat portion 379 may be shaped in such away that at least part of the outer circumference of the panel roller143 is depressed.

When the panel roller 143 rolls in the display panel 10, the source PCB120 may sit in the seat portion 379 and at least part of it may makecontact with the panel roller 143. Accordingly, the source PCB 120 maynot get damaged even if the panel roller 143 rolls in the display panel10.

The timing controller board 105 may be mounted inside the panel roller143. Mounting the timing controller board 105 inside the panel roller143 may prevent an FFC cable 117 connecting to the source PCB board 120from getting tangled.

The panel roller 143 may include an upper panel roller 331 and a lowerpanel roller 337. As an example, the upper panel roller 331 and thelower panel roller 337 may be held together with at least one screw. Thetiming controller board 105 may be mounted in between the upper panelroller 331 and the lower panel roller 337. The at least one screw mayhold the timing controller board 105 in place while holding the upperpanel roller 331 and the lower panel roller 337 together. The FFC cable117 may connect the timing controller board 105 with the source PCB 120via a hole in the upper panel roller 331.

The display device according to the embodiment of the present inventionallows for connecting the FFC cable 117 without it getting tangledbecause the timing controller board 105 rotates together with the panelroller 143, and also can save space because the timing controller board105 is mounted inside the panel roller 143.

Referring to FIG. 6, in the display device according to an embodiment ofthe present invention, the timing controller board 105 is mounted in thepanel roller 143 at one side of the center of the housing 30 where thedisplay panel ascends or descends, and a main board 109 and a powersupply 107 may be positioned on the other side of the center of thehousing 30.

The timing controller board 105 may be connected to the main board 109and the power supply 107. The timing controller board 105 may beconnected to the main board 109 and the power supply 107 through wireelectrodes 113. In more detail, the wire electrodes 113 may include afirst wire electrode 307 connecting the timing controller board 105 andthe power supply 107 and a second wire electrode 309 connecting thetiming controller board 105 and the main board 109.

For example, a plurality of first wire electrode 307 may be provided.Also, the first wire electrode 307 may have a round shape. The firstwire electrode 307 may connect the timing controller board 105 with thepower supply 107 via an opening in the center of the axis of rotation ofthe panel roller 143.

The second wire electrode 309 may use a flat flexible cable (FFC) cablethat connects the timing controller board 105 with the source PCB 120.The second wire electrode 309 may connect the timing controller board105 with the main board 109 via an opening in the center of the axis ofrotation of the panel roller 143.

The first wire electrode 307 and the second wire electrode 309 may bepositioned on opposite sides of the timing controller board 105. Theopenings leading to the first wire electrode 307 and the second wireelectrode 309 also may be positioned on opposite sides.

In the display device according to the embodiment of the presentinvention, the timing controller board 105 may be mounted in the panelroller 143, and the power supply 107 and the main board 109 may bepositioned on opposite sides of the display panel in the panel roller143. This can save a lot of space in the housing 30.

FIGS. 7 to 31 are views showing a display device according to anexemplary embodiment of the present invention.

Referring to FIG. 7, the display device according to the presentinvention may include the panel roller 143, motor assemblies 137, andsupports 73, within the housing 30.

The panel roller 143 may be positioned in front of where the displayportion 20 ascends or descends in the housing 30. The panel roller 143may wind or unwind the display panel 10 and the module cover 15simultaneously. Since the module cover 15 is thick, the diameter of thepanel roller 143 may increase a lot during a transition from the firststate to the second state. Accordingly, the panel roller 143 may bespaced a certain distance or farther apart from each side of the housing30, for instance, in the third direction.

The supports 73 may be positioned where the display portion 20 ascendsor descends. The supports 73 may function to support the display panel10 and the module cover 15 as they ascend or descend. In more detail,although not shown in this figure, the supports 73 may raise or lower atop bar attached to the top of the module cover 15 and display panel 10.A detailed method of operating the supports 73 will be described later.

Because only the top portions of the module cover 15 and display panel10 are connected to the top bar, the rest of them may bend easily.Accordingly, the supports 73 may support the module cover 15 from theback of the module cover 15 to keep the module cover 15 from bending.The supports 73 are not attached to the module cover 15 since they keepmoving during a transition from the first state to the second state.However, the supports 73 can still support the module cover 15.

The motor assemblies 137 may be positioned to connect with the supports73. The motor assemblies 137 may cause the supports 73 to ascend ordescend. The motor assemblies 137 may take electrical signals andconvert them into physical force. The motor assemblies 137 may transmitrotational energy to the supports 73, thereby making a transition fromthe first state to the second state. Detailed description of thestructure and operating principle of the motor assemblies 137 will begiven later.

In the display device according to the embodiment of the presentinvention, the display panel 10 and the module cover 15 may besimultaneously wound or unwound by one roller. This may lead to adecrease in the thickness of the housing 30, thus giving the user abetter view of the screen.

Referring to FIG. 8, the module cover 15 may include a plurality ofaprons. The aprons may be rectangular. The aprons may be spaced apartfrom one another and attached to the back of the display panel 10.Because the module cover 15 comprises of a plurality of aprons, itsshape may deform easily when it is wound around or unwound from theroller. The module cover 15 may include a plastic or aluminum material.Accordingly, the module cover 15 may protect the display panel 10 fromexternal impact.

The display panel 10 and the module cover 15 may be held together by anadhesion layer 70. The adhesion layer 70 may be double-sided tape. Usingthe adhesion layer 70, the module cover 15 may be wound or unwound alongwith the display panel 10. A segment of the adhesion layer 70 may bepositioned on an apron and adhere to the display panel 10. Each segmentof the adhesion layer 70 may be set apart from each other. Accordingly,the shape of the module cover 15 may deform easily when it is woundaround or unwound from the roller. The smaller the width of the adhesionlayer 70 along the second direction, the less the display panel 10 willdeform on external force. In more detail, the smaller the width of theadhesion layer 70 along the second direction, the more flexible it canbe, thus transmitting less external force on the display panel 10.

Moreover, the larger the width of the aprons along the second direction,the less likely the display panel 10 will have cracks. In more detail,the larger the width of the aprons along the second direction, thehigher the rigidity; thus, no cracks will appear in the display panel10.

Therefore, if the width of the adhesion layer 70 along the seconddirection is no more than 30% of the width of the aprons along thesecond direction, less external force is transmitted to the displaypanel 10, and this may lead to less bumps on the display screen.

Also, if the width of the adhesion layer 70 along the second directionis no less than 15% of the width of the aprons along the seconddirection, the rigidity of the display panel 10 is improved, and thismay lead to less cracks in the display panel 10.

Moreover, the larger the width of the adhesion layer 70 along the thirddirection, the less the display panel 10 will deform on external force.In more detail, the larger the width of the adhesion layer 70 along thethird direction, the more flexible it can be, thus transmitting lessexternal force on the display panel 10.

In addition, the smaller the width of the aprons along the thirddirection, the less likely the display panel 10 will have cracks. Inmore detail, the larger the width of the aprons along the thirddirection, the higher the rigidity; thus, no cracks will appear in thedisplay panel 10.

Therefore, if the width of the adhesion layer 70 along the thirddirection is no less than 3% of the width of the aprons along the thirddirection, less external force is transmitted to the display panel 10,and this may lead to less bumps on the display screen.

Also, if the width of the adhesion layer 70 along the third direction isno more than 6% of the width of the aprons along the third direction,the rigidity of the display panel 10 is improved, and this may lead toless cracks in the display panel 10.

In the display device according to the embodiment of the presentinvention, the module cover 15 may include a plurality of aprons, andthe adhesion layer 70 may sit on the aprons. Accordingly, the shape ofthe module cover 15 may deform more easily when it is wound around theroller, compared to when the module cover 15 is configured as a singleunit.

Referring to FIG. 9, in a display device according to another exemplaryembodiment of the present invention, the aprons may be in the shape ofparallelograms. That is, the aprons may be in the shape of rectanglesslanted in one direction. The aprons having the shape of parallelogramsmay prevent the display panel from bending in the opposite direction tothe direction in which the display panel is wound. Accordingly, thedisplay panel may remain flat in the second state.

When an external force is applied to the aprons in the oppositedirection 351 to the direction the display panel is wound, the apronsmay not rotate anymore because their surfaces come into contact with oneanother (see FIG. 9(a)). Accordingly, the display panel may remain flat.

In contrast, when an external force is applied to the aprons in thedirection 353 the display panel is wound, the aprons may rotate freelybecause their surfaces do not come into contact with one another (seeFIG. 9(b)). Accordingly, the display panel may be wound or unwound withease.

In the display device according to the embodiment of the presentinvention, the aprons may rotate only in one direction. Accordingly, thescreen will not bend even if an external force is applied to the displaypanel.

Referring to FIG. 10, in the display device according to an embodimentof the present invention, the module cover 15 and the display panel 10may be fastened to a top bar 75. For example, the module cover 15 andthe display panel 10 may be fastened to the top bar 75 with at least onescrew 115.

The at least one screw 115 allows the module cover 15 and the displaypanel 10 to ascend or descend together with the top bar 75, withoutdeviating from each other. The at least one screw 115 may fasten the topbar 75 and the module cover 15 together and fasten the top bar 75 andthe display panel 10 together. However, the at least one screw 115 isnot limited to such a configuration, but may fasten the module cover 15and the display panel 10 together.

An upper module cover 15 t of the module cover 15 may differ in shapefrom the rest of the module cover 15 so as to be attached to the top bar75. The upper module cover 15 t may be the uppermost apron. In moredetail, the uppermost apron may have a different shape than the otheraprons. At least a part of the upper module cover 15 t may have adifferent thickness from the rest along the third direction. The parthaving a different thickness from the rest may be inserted into a recessof the top bar 75.

The part having a different thickness from the rest of the upper modulecover 15 t may be fastened to the top bar 75, for example, by at leastone screw 115. Since the upper module cover 15 t is inserted into thetop bar 75, the module cover 15 may be fastened more firmly to the topbar 75.

As illustrated in FIG. 10(b), the top bar 75, the module cover 15, andthe display panel 10 may be covered by a top case 167. The top case 167may shield the top bar 75, the module cover 15, and the display panel 10on both sides and the top. The at least one screw 115 may fasten the topcase 167, together with the top bar 75, the module cover 15, and thedisplay panel 10. However, the top case 167 is not limited to such aconfiguration, but may be inserted into recesses in the top bar 75,module cover 15, and display panel 10.

In the display device according to the embodiment of the presentinvention, the top bar 75, the module cover 15, and the display panel 10may be held together. Accordingly, the module cover 15 and the displaypanel 10 may ascend or descend easily without deviating from each other.

Moreover, the top case 167 may cover the top bar 75, the module cover15, and the display panel 10. Thus, the user may find the look of thedisplay device more neat and tidy.

Referring to FIG. 11, the display device according to an embodiment ofthe present invention may be so shaped that both sides of the top bar 75are supported by the supports 73. The top bar 75 may ascend or descendby means of the supports 73. Each support 73 may include an upper link73 a and a lower link 73 b.

The upper link 73 a and the lower link 73 b may be connected by a hinge152. One end of the upper link 73 a may be fastened to the top bar 75and the other end to the hinge 152, and one end of the lower link 73 bmay be fastened to the motor assembly and the other end to the hinge152.

A guide bar 234 may be positioned at the entrance where the supports 73ascend from or descend into the housing. The guide bar 234 may includefirst and second guide bars 234 a and 234 b. The first and second guidebars 234 a and 234 b may face each other, with the supports 73 inbetween. For example, the first guide bar 234 a may be positioned infront of the supports 73, and the second guide bar 234 b may bepositioned behind the supports 73.

The panel roller 143 may be positioned at the bottom, in front of thesupports 73. The panel roller 143 may be provided with at least onebracket 221 corresponding to the bottom surface of the housing. Forexample, at least one bracket 221 may be positioned below the panelroller 143. The at least one bracket 221 may be spaced apart from oneanother. For example, the at least one bracket 221 may be fixed to thebottom surface of the housing with screws.

The display device according to the embodiment of the present inventionmay have various operating mechanisms in it. This may reduce the risk ofbreakdown that may occur when the display panel ascends or descends bymeans of the roller.

Referring to FIG. 12, the first guide bar 234 a may guide the displaypanel 10 and module cover 15 wound around the panel roller 143 at a partof the housing 30 where they ascend or descend. Accordingly, the displaypanel 10 and the module cover 15 may ascend or descend from a desiredposition even if their position does not correspond to where the panelroller 143 ascends or descends the display panel 10 and the module cover15. The display panel 10 and the module cover 15, both in the first andsecond states, may come into contact with the first guide bar 234 a atthe entrance of the housing 30. Accordingly, the display panel 10 andthe module cover 15 may ascend or descend from the same positionregardless of which state they are in.

The bracket 221 may be positioned below the panel roller 143. A side ofthe bracket 221 facing the panel roller 143 may be concaved. The bracket221 may guide the display panel 10 and module cover 15 wound around thepanel roller 143 in such a way that they are not dragged against thebottom surface of the housing 30. Accordingly, the diameter BD of theconcaved portion of the bracket 221 may be larger than the diameter RDof the panel roller 143. If the diameter BD of the concaved portion ofthe bracket 221 is smaller than the diameter RD of the panel roller 143,the display panel 10 and the module cover 15 may deviate from thebracket 221 and be dragged against the bottom surface of the housing 30.The bracket 221 may include rubber or plastic in order to prevent damagedue to friction with the display panel 10 and the module cover 15.

Referring to FIG. 13, in the case that the bracket 221 is not providedas shown in FIG. 13(a), when the display panel 10 and the module cover15 are unwound from the panel roller 143, they may be dragged againstthe bottom surface of the housing 30. Accordingly, the display panel 10or the module cover 15 may have cracks. Also, the display panel 10 andthe module cover 15 may not be freely wound.

In contrast, in the case that the bracket 221 is positioned below thepanel roller 143 as shown in FIG. 13(b), when the display panel 10 andmodule cover 15 are unwound from the panel roller 143, they may makecontact with the bracket 221. Since the concaved portion of the bracket221 has a semicircular shape, the display panel 10 and the module cover15 may keep their rolled shape, rather than hanging down. Also, thebracket 221 may prevent the display panel 10 and the module cover 15from damage due to friction with the housing 30.

Referring to FIG. 14, in the display device according to an embodimentof the present invention, the top bar 75 may ascend during a transitionfrom the first state to the second state. The top bar 75 may ascend ordescend as it is pushed by the supports 73 on two opposite edges.

As illustrated in FIG. 14(a), in the first state, the angle HRA betweenthe upper link 73 a and the lower link 73 b may be very small. Thus, thetop bar 75 has not ascended. Also, the display panel and the modulecover may be kept wound around the panel roller.

As illustrated in FIG. 14(b), as the motor assembly 137 rotates, theangle HRA between the upper link 73 a and the lower link 73 b mayincrease. An increase in the angle HLA between the upper link 73 a andthe lower link 73 b may allow the top bar 74 to ascend. Accordingly, thedisplay panel and module cover wound around the panel roller may becomegradually unwound.

As illustrated in FIG. 14(c), in the second state, the upper link 73 aand the lower link 73 b may be parallel to each other. That is, theangle HLA between the upper link 73 a and the lower link 73 b may be 180degrees. Accordingly, the top bar 75 may be at the maximum height. Also,the display panel and the module cover may become fully unwound from thepanel roller.

Referring to FIG. 15, in the display device according to the embodimentof the present invention, a stand fixing portion 315 and a stand 317 maybe positioned behind the motor assembly.

The stand fixing portion 315 may be positioned corresponding to themotor assembly 137 and shield the motor assembly 137. The stand fixingportion 315 may be fastened to the motor assembly 137 and the housing 30so that the stand 317 is fixed to the housing 30.

Since the stand fixing portion 315 and the stand 317 correspond to themotor assembly 137, they may be positioned on either side of the displaydevice.

The stand 317 may be connected to the stand fixing portion 315 and beexposed to the outside of the housing 30. The stand 317 may have theshape of a cylinder extending in one direction. The stands 317 on bothsides of the display device may serve as legs of the display device.That is, the stands 317 may serve to support the display device.

The stand 317 may rotate with respect to the stand fixing portion 315.Accordingly, the user may rotate the stand 317 to bring the bottomsurface of the housing 30 into contact with the ground. That is, thestand 317 may be rotated in such a way as to not make contact with theground such that the height of the display panel 10 corresponds to theheight of the user's eyes In this case, the user may adjust the heightof the display panel 10 to the height of their eyes by rotating thestand 317.

Referring to FIG. 16, in the display device according to the embodimentof the present invention, the upper link 73 a may comprise of multipleparts, and likewise the lower link 73 b may comprise of multiple parts.

In more detail, the upper link 73 a may include a first upper link 73Caand a second upper link 73Fa. Likewise, the lower link 73 b may includea first lower link 73Cb and a second lower link 73Fb.

The first upper and lower links 73Ca and 73Cb may be positioned furtheroutward than the second upper and lower links 73Fa and 73Fb. The firstupper and lower links 73Ca and 73Cb may be connected to the center ofthe hinge 152, and the second upper and lower links 73Fa and 73Fb may beconnected to both sides of the hinge 152.

The end portions of the first upper and lower links 73Ca and 73Cb insidethe hinge 152 may be in the shape of gears meshing with each other. Thehinge 152 may hold the first upper link 73Ca and the first lower link73Cb in place so that the gears of the first upper and lower links 73Caand 73Cb mesh with each other.

The angle HRA1 from the horizontal line passing between the first upperlink 73Ca and the first lower link 73Cb (ground) to the first upper link73Ca, and the angle HRA2 from the ground to the first lower link 73Cbmay be equal because the first upper link 73Ca and the first lower link73Cb are in the shape of gears meshing with each other and symmetricwith respect to the ground. Also, the angle between the first upper link73Ca and the first lower link 73Cb may be equal for support 73 of bothhinges 152. Accordingly, the top bar 75 operated by the upper link 73 aand the lower link 73 b of support 73 of both hinges 152 may ascend ordescend to the same height without misalignment. That is, the anglebetween the first upper link 73Ca and the first lower link 73Cb may beequal on both hinges 152, regardless of which state the display panel isin.

The second upper and lower links 73Fa and 73Fb may support the firstupper and lower links 73Ca and 73Cb on the inside of the second upperand lower links 73Fa and 73Fb. The angle between the second upper link73Fa and the second lower link 73Fb may change the same way as the anglebetween the first upper link 73Ca and the first lower link 73Cb does.

Referring to FIG. 17, in a display device according to a previousembodiment of an invention, the upper and lower links 73 a and 73 b wereconfigured as a single link, as illustrated in FIG. 17(a). Accordingly,when an external force F was applied to one side of the display panel,the angle HRA between the upper and lower links 73 a and 73 b on thatside became distorted. Accordingly, the angle HRA between the upper andlower links 73 a and 73 b differed between the two hinges. In this case,one side of the display panel became slanted as illustrated in FIG.17(b).

In contrast, in the display device according to the embodiment of thepresent invention, the second upper and lower links 73Fa and 73Fb maysupport the first upper and lower links 73Ca and 73Cb even if anexternal force F is applied to one side of the display panel, asillustrated in FIG. 17(c). Accordingly, the angle HRA between the upperand lower links 73 a and 73 b may not change. In this case, the displaypanel may be kept from slanting, allowing the user to immerse themselvesin the display screen without distraction. Moreover, any damage due tothe slant of the display panel may be prevented.

Referring to FIG. 18, in the display device according to an embodimentof the present invention, one side of the first upper and lower links73Ca and 73Cb may be extended toward the second upper and lower links73Fa and 73Fb. That is, the width of the first upper and lower links73Ca and 73Cb may be increased and larger when viewed from the front(away from the hinge side). Accordingly, the first upper and lower links73Ca and 73Cb may shield the second upper and lower links 73Fa and 73Fbin the front.

The rotational axis of the first upper and lower links 73Ca and 73Cb maybe at a different height from that of the second upper and lower links73Fa and 73Fb. In more detail, the rotational axis of the first upperand lower links 73Ca and 73Cb may be at a different height from that ofthe second upper and lower links 73Fa and 73Fb, along the thirddirection (z direction). That is, the vertical height of a portion ofthe hinge 152 that is connected to the first upper and lower links 73Caand 73Cb may be different from the vertical height of a portion of thehinge 152 that is connected to the second upper and lower links 73Fa and73Fb. Accordingly, even if one side of the first upper and lower links73Ca and 73Cb extends toward the second upper and lower links 73Fa and73Fb, the first upper and lower links 73Ca and 73Cb may not come intocontact with the second upper and lower links 73Fa and 73Fb.

Although not shown, one side of the second upper and lower links 73Faand 73Fb may be extended toward the first upper and lower links 73Ca and73Cb. That is, the width of the second upper and lower links 73Fa and73Fb may be increased and larger when viewed from the rear (toward thehinge side). Accordingly, the second upper and lower links 73Fa and 73Fbmay shield the first upper and lower links 73Ca and 73Cb in the front.

Referring to FIG. 19, in the first state, the first upper and lowerlinks 73Ca and 73Cb and the second upper and lower links 73Fa and 73Fbmay overlap, respectively, at least partially in width, as illustratedin FIG. 19(a). For example, the first upper and lower links 73Ca and73Cb and the second upper and lower links 73FA and 73Fb may partiallyoverlap such that there is a certain distance SLD between the firstupper link 73Ca and the second upper link 73Fa, and a certain distanceSLD between the first lower link 73Cb and the second lower link 73Fb.Accordingly, the entire width of the upper link 73 a may be larger thanthe width HLW of the second upper link 73Fa or the width CLW of thefirst upper link 73Ca.

In contrast, as illustrated in FIG. 19(b), in the second state, thefirst upper and lower links 73Ca and 73Cb and the second upper and lowerlinks 73Fa and 73Fb may overlap fully in width with each other. Forexample, the first upper and lower links 73Ca and 73Cb and the secondupper and lower links 73FA and 73Fb may fully overlap such that there isno certain distance SLD between the first upper link 73Ca and the secondupper link 73Fa, and no certain distance SLD between the first lowerlink 73Cb and the second lower link 73Fb. Accordingly, the entire widthHLW of the upper link 73 a may be equal to the width of the second upperlink 73Fa or the width CLW of the first upper link 73Ca.

Referring to FIG. 20, in the case that one side of the first upper link73Ca is not extended toward the second upper link 73Fa, the first upperlink 73Ca and the second upper link 73Fa may be spaced a certaindistance LD apart from each other as the first upper link 73Ca is movedfrom the first state to the second state, as illustrated in FIG. 20(a).The distance LD between the first upper link 73Ca and the second upperlink 73Fa may increase when moving from the first state toward thesecond state.

The problem with this is that the user's hand may get hurt by gettingcaught between the first upper link 73Ca and the second upper link 73Faduring the transition from the first state to the second state.

In contrast, as illustrated in FIG. 20(b), in the case that one side ofthe first upper link 73Ca is extended toward, and overlapping with thesecond upper link 73Fa, the space between the first upper link 73Ca andthe second upper link 73Fa may not be exposed even when the first upperlink 73Ca is moved from the first state to the second state. This canavoid the risk of the user's hand getting caught between the first upperlink 73Ca and the second upper link 73Fa during the transition from thefirst state to the second state.

Referring to FIG. 21, the motor assembly 137 may include a motor 138 anda decelerator 139.

The motor 138 may take electricity and convert them into physical force.The motor may transmit rotational energy to the decelerator 139. Theremay be two motors 138 which may be fixed to the bottom of either side ofthe housing 30.

The decelerator 139 may be shaped to interlock with the motor 138. Thedecelerator 139 may be covered in a different casing from the motor 138.With the decelerator 139 being covered in a different casing from themotor 138, unnecessary contact between them may be avoided. However, thedecelerator 139 is not limited to such a configuration, but may becovered in the same casing as the motor 138.

The decelerator 139 may rotate in the first direction when the motor 138rotates in the first direction, and rotate in the second direction whenthe motor 138 rotates in the second direction. The decelerator 139 maytransmit a large amount of rotational energy while lowering the rotationspeed of the motor 138.

When the decelerator 139 rotates in the first direction, the angle fromthe ground to the lower link 73 b connected to the decelerator 139 mayincrease. When the decelerator 139 rotates in the second direction, theangle from the ground to the lower link 73 b connected to thedecelerator 139 may decrease.

Referring to FIG. 22, in the display device according to an embodimentof the present invention, the lower link 73 b may be pushed using atransmission portion 126 connected to an auxiliary link 191. Theauxiliary link 191 may include a fastening portion 151, a cylindricalportion 153, and a spring portion 179.

One end of the transmission portion 126 may be connected to a lower partof the first lower link 73Cb and push the first lower link 73Cb. Thetransmission portion 126 may transmit energy from the auxiliary link 191to the first lower link 73Cb. The other end of the transmission portion126 may be connected to the fastening portion 151 of the auxiliary link191.

A guide wheel 241 may be positioned at the joint of the transmissionportion 126 and the auxiliary link 191. The guide wheel 241 may guidethe transmission portion 126 and the auxiliary link 191 during thetransition from the first state to the second state in such a way thatthey do not deviate in the third direction. Since the guide wheel 241guides the transmission portion 126 and the auxiliary link 191 in thisway, the force of the auxiliary link 191 may be correctly transmitted tothe first lower link 73Cb.

The fastening portion 151 may be a portion that attaches the auxiliarylink 191 and the transmission portion 126 together. The fasteningportion 151 may transmit elastic force to the transmission portion 126.

The spring portion 179 may push the fastening portion 151. The springportion 179 may be compressed when the lower link 73 b descends, andstretched when the lower link 73 b ascends. Thus, the spring portion 179may exert force using its elasticity when the lower link 73 b ascends.

Without the spring portion 179, the lower link 73 b receives force onlyfrom the motor 138. If the angle from the ground to the lower link 73 bis close to 0°, a considerable amount of torque may be needed. Thus, themotor 138 will require quite a large amount of force. This will requirethe motor 138 to be large in size, and also will require a large housingsize.

On the other hand, with the spring portion 179, much less torque may berequired to make the lower link 73 b ascend. Thus, the force requiredfor the motor 138 may be reduced to a considerable extent. This canreduce the size of the motor and also the size of the housing foraccommodating the motor 138. With such a reduction in the size of thehousing, the display device may enable the user to immerse themselves inthe display panel without distraction by the size of the housing.

The cylindrical portion 153 may shield at least part of the fasteningportion 151 and the spring portion 179. Accordingly, the cylindricalportion 153 may exert force to the fastening portion 151 withoutdeviating when the spring portion 179 is stretched due to itselasticity.

In the display device according to the embodiment of the presentinvention, this elasticity allows the auxiliary link 191 to push thelower link 73 b. Accordingly, the top bar 75 may ascend more easily.

Referring to FIG. 23, the guide wheel 241 may move on a guide rail 372during the transition from the first state to the second state. Theguide rail 372 may be depressed inward in the center of the guide rail372, and the guide wheel 241 may be inserted in the depressed part ofthe guide rail 372 and be movable.

As illustrated in FIG. 23(a), in the first state, most of the fasteningportion 151 may be within the cylindrical portion 153. This means thatthe spring portion is compressed. Since the fastening portion 151 doesnot push the transmission portion 126, the angle from the ground to thetransmission portion 126 may be small. The guide wheel 241 may bepositioned adjacent to the cylindrical portion 153, along the guide rail372.

As illustrated in FIG. 23(b), the fastening portion 151 may be exposedout of the cylindrical portion 153 during the transition from the firststate to the second state. That is, the fastening portion 151 may pushthe transmission portion 126. In this case, the spring portion maydeliver elastic energy as it is uncompressed. Since the fasteningportion 151 pushes the transmission portion 126, the angle from theground to the transmission portion 126 may increase gradually. The guidewheel 241 may be positioned midway along the guide rail 372.

As illustrated in FIG. 23(c), in the second state, most of the fasteningportion 151 may be exposed out of the cylindrical portion 153. Thismeans that the spring portion is fully uncompressed. Since the fasteningportion 151 pushes the transmission portion 126, the angle from theground to the transmission portion 126 may be large. The guide wheel 241may be positioned adjacent to the lower link 73 b, along the guide rail372.

In the display device according to the embodiment of present invention,the guide wheel 241 may push the lower link 73 b while moving along theguide rail 372. Accordingly, the elasticity of the spring portion may betransmitted more easily and correctly.

Referring to FIG. 24, the spring portion 179 may include first to thirdsprings 179 a to 179 c. The first spring 179 a may be more adjacent tothe fastening portion 151 than the second and third springs 179 b and179 c. Also, the second spring 179 b may be more adjacent to thefastening portion 151 than the third spring 179 c. That is, the thirdspring 179 c may be the farthest spring from the fastening portion 151.Accordingly, the third spring 179 c may be the farthest spring from thetransmission portion connected to the fastening portion 151.

At least one of the first to third springs 179 a to 179 c may have adifferent spring constant. For example, the third spring 179 c may havea higher spring constant than the first and second springs 179 a and 179b. That is, the third spring 179 c requires more force to deform thanthe first and second springs 179 a and 179 b. The first to third springsmay be separated from one another by side supporters 182 and mainsupporters 184.

The side supporters 182 may include first and second side supporters 182a and 182 b. The first side supporter 182 a may be positioned on one endof the first spring 179 a, and the second side supporter 182 b may bepositioned on the other end of the third spring 179 c. Protrusions ofthe first and second side supporters 182 a and 182 b may be insertedinto the first and third springs 179 a and 179 c.

The main supporters 184 may include first and second main supporters 184a and 184 b. The first main supporters 184 a may be positioned betweenthe first spring 179 a and the second spring 179 b.

The first and second main supporters 184 a and 184 b may protrude onboth sides. Protrusions of the first main supporter 184 a may beattached to the other end of the first spring 179 a and one end of thesecond spring 179 b. Also, protrusions of the second main supporter 184b may be inserted into the other end of the second spring 179 b and oneend of the third spring 179 c.

The range of displacement of the first to third springs 179 a to 179 cmay be limited due to the side supporters 182 and the main supporters184. That is, the amount of compression of the first to third springs179 a to 179 c may be limited due to the side supporters 182 and themain supporters 184.

In the display device according to the embodiment of the presentinvention, the spring portion 179 may comprise of a plurality of springswith different spring constants. Accordingly, the force the springportion 179 exerts may be balanced with the non-linear force needed forthe supports to ascend or descend.

Referring to FIGS. 25 and 26, in the second state, the spring portion179 may be in an uncompressed state. Accordingly, the spring portion 179may have a first length SD1. The first length SD1 may be the maximumlength when the spring portion 179 is fully uncompressed. Theuncompressed spring portion 179 may transmit force to the supports 73 bypushing on the fastening portion 151.

During the transition from the second state to the first state, theangle from the ground to the lower link 73 b may decrease, pushing thetransmission portion 126 toward the center. Accordingly, the force istransmitted to the fastening portion 151, allowing the fastening portion151 to compress the spring portion 179. The spring portion 179 may havea second length SD2, which is shorter than the first length SD1 thespring portion 179 had in the second state.

In the second state, the spring portion 179 may not be exposed out ofthe cylindrical portion 153. That is, the spring portion 179 may not beexposed out of the cylindrical portion 153 in any circumstances. Sincethe spring portion 179 is not exposed out of the cylindrical portion153, it may push the lower link 73 b without deviating from thecylindrical portion 153. Also, since the spring portion 179 is notexposed out of the cylindrical portion 153, its elasticity is notscattered and the user will find the look of the display device tidy.

Referring to FIG. 27, if the side supporters 182 and the main supporters184 are not provided among the first to third springs 179 a to 179 c, asillustrated in FIG. 27(a), the first and second springs 179 a and 179 bwith a lower spring constant may be excessively compressed in the firststate. In contrast, the amount of compression of the third spring 179 cwith a higher spring constant may be relatively small in the firststate, compared to the first and second springs 179 a and 179 b.

In this case, the first and second springs 179 a and 179 b may sufferplastic deformation due to the excessive compression. Also, the amountof compression of the third spring 179 c may be relatively small. Due tothe plastic deformation of the first and second springs 179 a and 179 b,the first and second springs 179 a and 179 b may not be restored totheir original length during the transition from the first state to thesecond state. That is, the length of the first and second springs 179 aand 179 b may be shorter than that before the plastic deformation by acertain distance SDD. Accordingly, the spring portion 179 does not pushon the fastening portion 151 and therefore the lower link 73 b may notascend.

On the other hand, as illustrated in FIG. 27(b), when the sidesupporters 182 and the main supporters 184 are provided among the firstto third springs 179 a to 179 c, the amount of compression of the firstto third springs 179 a to 179 c in the first state may be limited due tothe side supporters 182 and the main supporters 184. That is, the firstand second springs 179 a and 179 b may be compressed no more than acertain length. Thus, the first and second springs 179 a and 179 b maynot suffer physical deformation even when they are compressed. Also, thecompression force may not be concentrated on the first and secondsprings 179 a and 179 b. Accordingly, the length of the spring portion179 may be longer if the side supporters 182 and the main supporters 184are provided.

The first and second springs 179 a and 179 b may not suffer plasticdeformation because of the side supporters 182 and the main supporters184. Thus, the first and second springs 179 a and 179 b may return totheir original length after the transition from the first state to thesecond state. Accordingly, the spring portion 179 may properly push onthe fastening portion 151, allowing the lower link 73 b to ascend.

In the display device according to the embodiment of the presentinvention, the side supporters 182 and the main supporters 184 may bepositioned among the springs. Accordingly, the spring portion 179 maynot suffer plastic deformation, which makes it easy to transmit force tothe lower link 73 b.

Referring to FIG. 28, in the display device according to an embodimentof the present invention, a roller hub 278 may be positioned on eitherside of the housing, corresponding to the panel roller 143. The rollerhub 278 may be attached to the center axis of the panel roller 143. Theroller hub 278 may have a wide circumference so that a transmission belt314 to be described later may easily wound around it.

A constant spring 316 may be spaced apart from the roller hub 278. Thetransmission belt 314 may be wound around the constant spring 316 andthe roller hub 278. The transmission belt 314 may tend to remain woundaround the constant spring 316. Accordingly, if the transmission belt314 is unwound from the constant spring 316, force may be exerted in adirection in which the transmission belt 314 is to be wound again.

The constant spring 316 may be located a first distance CSD below theroller hub 278, along the second direction. In this case, more force maybe transmitted, compared to when the constant spring 316 is at the sameheight as or above the roller hub 278.

Referring to FIG. 29, a first torque T1 may be applied to the panelroller 143 to wind the display panel around the panel roller 143, asillustrated in FIG. 29(a). Since the first torque T1 is small, theamount of rotation of the panel roller 143 may be relatively small,compared to the length of vertical movement of the display panel 10. Inthis case, the display panel 10 may hang down from the panel roller 143and thus may not be correctly wound around the panel roller 143.

As illustrated FIG. 29(b), a second torque T2 may be applied to thepanel roller 143 to wind the display panel 10 around the panel roller143. The second torque T2 may be larger than the first torque T1.Accordingly, the amount of rotation of the panel roller 143 maycorrespond to the length of vertical movement of the display panel 10.In this case, the display panel 10 may be correctly wound around thepanel roller 143 as they interlock with each other.

In the display device according to the embodiment of the presentinvention, a certain amount of torque or more may be required in orderthat the display panel 10 is correctly around the panel roller 143 byinterlocking with it. Accordingly, a device for applying the certainamount of torque or more to the panel roller 143 may be required.

Referring to FIG. 30, the roller hub 278 may rotate together with thepanel roller 143 in a first direction, i.e., counterclockwise direction,during the transition from the first state to the second state, asillustrated in FIG. 30(a). The display panel 10 and the transmissionbelt 314 may be kept wound in opposite directions. Accordingly, as thedisplay panel 10 and the roller hub 278 rotate in the first direction,the transmission belt 314 may be unwound from the roller hub 278 and thedisplay panel 10 may be wound around the panel roller 143.

Because the constant spring 316 has a certain amount of torque in aclockwise direction, it may help the display panel 10 rotatecounterclockwise when it is wound around the roller hub 278. Since thetorque of the constant spring 316 helps when the roller hub 278 rolls,it may help also when the panel roller 143 connected to the roller hub278 rolls. Accordingly, the display panel 10 may be correctly woundaround the panel roller 143 by interlocking with it.

In contrast, as illustrated in FIG. 30(b), the roller hub 278 may rotatetogether with the panel roller 143 in a second direction, which is theopposite direction to the first direction, during the transition fromthe first state to the second state. The display panel 10 and thetransmission belt 314 may be kept wound in opposite directions.Accordingly, as the display panel 10 and the roller hub 278 rotate inthe second direction, the transmission belt 314 may be wound around theroller hub 278 and the display panel 10 may be unwound from the panelroller 143.

Because the constant spring 316 has a certain amount of torque in aclockwise direction, it may obstruct the display panel 10 from rotatingclockwise when unwound from the roller hub 278. Accordingly, the forcerequired for the display panel 10 to ascend by means of the supportsshould be larger than the torque of the constant spring 316, in orderfor the constant spring 316 not to obstruct the panel roller 143 and theroller hub 278 from rotating in the second direction.

In the display device according to the embodiment of the presentinvention, when the panel roller 143 and the roller hub 278 rotate inthe second direction, the display panel 10 may be wound fast by thetorque of the constant spring 316. This may prevent the display panel 10from hanging down from the panel roller 143.

Referring to FIG. 31, the torque of a conventional torsion spring versusthe number of rotations of the roller hub is indicated with a dottedline, and the torque of the constant spring versus the number ofrotations of the roller hub is indicated with a solid line.

The amount of change in the torque required to wind the display panelaround the panel roller may be small depending on the number ofrotations.

As indicated with the dotted line, the greater the number of rotations,the larger the torque applied to the conventional torsion spring.Accordingly, unnecessary torque may be produced. This may requiremechanisms for reducing unnecessary torque, and the addition of thesemechanisms may increase noise.

On the other hand, as indicated with the solid line, the torque appliedto the constant spring may be constant if the number of rotationsexceeds a certain value. Accordingly, unnecessary torque may beminimized, and this may lead to less noise and minimum installationspace.

FIGS. 32 to 43 are views showing a display device according to anotherexemplary embodiment of the present invention.

Referring to FIG. 32, in the display device according to an embodimentof the present invention, the panel roller 143 may be positioned infront of the supports 73, and an apron roller 141 may be positionedbehind the supports 73. That is, the panel roller 143 and the apronroller 141 may face each other on opposite sides of the supports 73.

The panel roller 143 may wind or unwind the display panel 10, and theapron roller 141 may wind or unwind the module cover 15. The displaypanel 10 and the module cover 15 may not be attached with an adhesionlayer because they are wound around different rollers.

The module cover 15 may be thicker than the display panel 10, so it maytake up a lot of space in the housing 30. Accordingly, the motorassemblies 137 may be positioned in front of the supports 73 so as tonot obstruct the winding or unwinding of the module cover 15. However,the motor assemblies 137 are not limited to such a configuration, butmay be positioned behind the supports 73.

As the display panel 10 and the module cover 15 are separately woundwithin the housing 30, the winding force of the panel roller 143 andapron roller 141 may be greater than the attachment force of the displaypanel 10 and module cover 15.

In the embodiment of the present invention, the display panel 10 and themodule cover 15 may be wound by two rollers, respectively. Accordingly,the weight of windings may be shared between the two rollers, and thismay prevent the display panel 10 and the module cover 15 from hangingdown during winding.

Referring to FIG. 33, in the display device according to an embodimentof the present invention, the panel roller 143 and the apron roller 141may be positioned on the same side. For example, the panel roller 143and the apron roller 141 may be positioned behind the supports 73.However, the panel roller 143 and the apron roller 141 are not limitedto such a configuration, but may be positioned in front of the supports73.

The apron roller 141 may be positioned below the panel roller 143. Sincethe module cover 15 has a large thickness, the diameter of the apronroller 141 may increase quite a lot during the transition from thesecond state to the first state. Accordingly, the apron roller 141 maybe spaced a first distance PGD or longer apart from the panel roller 143to avoid contact with the panel roller 143. The distance PGD may beequal to or greater than the distance at which the apron roller 141, inthe first state, does not make contact with the panel roller 143.

A guide roller 145 may be positioned in a line along which the apronroller 141 unrolls. The guide roller 145 may guide the module cover 15in such a way that the module cover 15 does not make contact with thepanel roller 143 when the module cover 15 is in at least one of thefirst and second states. The guide roller 145 may be positioned belowthe panel roller 143 so that the module cover 15 does not make contactwith the panel roller 143.

In the display device according to the embodiment of the presentinvention, the panel roller 143 and the apron roller 141 may bepositioned one above the other on the same side. This may save morespace compared to when the panel roller 143 and the apron roller 141 areon different sides.

Referring to FIG. 34, in the display device according to the embodimentof the present invention, a pressure roller 147, instead of the guideroller, may be provided. The pressure roller 147 may press the modulecover 1 into contact with the supports 73. Accordingly, the module cover15 may remain flat without being bent. The pressure roller 147 may bepositioned adjacent to the supports 73 in a third direction so that themodule cover 15 makes contact with the supports 73. The pressure roller147 may function to guide the module cover 15 so that the module cover15 and the panel roller 143 make contact with each other.

In the display device according to the embodiment of the presentinvention, the pressure roller 147 may press the module cover 15 intocontact with the supports 73. Accordingly, the display panel 10 maybecome flat, allowing the user to immerse themselves in the displaypanel 10.

Referring to FIG. 35, in the display device according to an embodimentof the present invention, both the guide roller 145 and the pressureroller 147 may be provided. Thus, the module cover 15 may be kept frommaking contact with the panel roller 143, but may come into contact withthe supports 73. This may result in fewer malfunctions in the displaydevice, and the user may enjoy watching on the flat surface of thedisplay panel 10.

Referring to FIG. 36, in the display device according to an embodimentof the present invention, the module cover 15 may include a plurality ofsections such as a first to fourth module cover sections 15 a to 15 d.

The first module cover section 15 a may be positioned in the center ofthe module cover 15. The first module cover section 15 a may be attachedto the top bar 75. An exemplary method of attaching the first modulecover section 15 a will be described later. The third module coversection 15 c may be positioned on either side of the module cover 15.That is, the third module cover section 15 c may be positioned on eachside of the module cover 15.

The fourth module cover section 15 d may be positioned on the top sideof the module cover 15. The fourth module cover section 15 d may beconnected to the upper part of the third module cover section 15 c. Inthe second state, the fourth module cover section 15 d and the thirdmodule cover section 15 c may be positioned on the rear edge of thedisplay panel. The fourth module cover section 15 d may be attached tothe top bar 75. For example, the fourth module cover section 15 d mayhave a shape that covers the top bar 75 in the rear. An exemplary methodof attaching the fourth module cover section 15 d may be describedlater.

The second module cover section 15 b may be positioned further back fromthe first module cover section 15 a and third module cover section 15 c,and may be attached to the first and third module cover sections 15 aand 15 c. The center of the second module cover section 15 b may beattached to the first module cover section 15 a, and both sides of thesecond module cover section 15 b may be attached to the third modulecover section 15 c.

The first module cover section 15 a and the third module cover section15 c may be spaced apart from each other. Also, the front of the firstmodule cover section 15 a may protrude a certain distance LMD from thefront of the second module cover section 15 b. That is, the first modulecover section 15 a and the third module cover section 15 c may havespace in between. The supports 73 may be positioned in the space betweenthe first module cover section 15 a and the third module cover section15 c.

Although not shown, the display panel 10 may be attached to the front ofthe module cover 15. Accordingly, the supports 73 may be shielded by thedisplay panel 10 in the front and by the second module cover section 15b in the rear. The user may immerse themselves in the display screenbecause the operation of the supports 73 is out of their view, and willfind the look of the display device tidy.

Referring to FIG. 37, without the first module cover section 15 a, thedisplay panel 10 is attached only to the third module cover section 15 con both sides, as illustrated in FIG. 37(a). Thus, the display panel 10may be depressed in the center, because of a space between the secondmodule cover section 15 b and the display panel 10.

Accordingly, the user may not be able to immerse themselves in thedisplay screen because of the non-flatness of the surface of the displaypanel 10. Also, the depression may lead to damage to the display panel.

In contrast, in the display device according to the embodiment of thepresent invention, the first module cover section 15 a may be positionedin the center, as illustrated in FIG. 37(b). The display panel 10 may beattached to the third module cover section 15 c on both sides, and itscenter may be attached to the first module cover section 15 a. The firstmodule cover section 15 a will occupy a space between the display panel10 and the second module cover section 15 b. As such, the display 10 mayremain flat. Accordingly, the user can immerse themselves in the displayscreen.

Referring to FIG. 38, in the display device according to an embodimentof the present invention, the third module cover section 15 c positionedon both sides of the module cover may be attached to the display panel10.

The third module cover section 15 c and the display panel 10 may be heldtogether by magnets 64 positioned on at least one apron. The magnets 64may be attached to the apron with double-sided tape. The magnets 64 maybe spaced apart from one another. Thus, their shape may be easilydeformed when the module cover 15 is wound by the roller or unwound fromit.

The display panel 10 may be attached to the magnets 64. The surface ofthe display panel 10 that makes contact with the magnets 64 may includea Fe—Ni Invar alloy. Accordingly, the display panel 10 may be firmlyattached to the magnets 64. It should be noted that the surface of thedisplay panel that makes contact with the magnets 64 could be a metallicmaterial that attaches to a magnet.

Since the display panel 10 and the module cover are attached by themagnets 64, which are positioned only on both sides of the module cover15, only a small number of magnets 64 are required. This will savemanufacturing costs.

Referring to FIG. 39, in the display device according to an embodimentof the present invention, the magnets 64 may be positioned in recesses118 of the third module cover section 15 c.

The recesses 118 may be positioned on the side of the display panel 10facing the third module cover section 15 c. The recesses 118 may bepositioned in the respective aprons. Since the magnets 64 are positionedin the recesses 118, the surfaces of the aprons that are in contact withthe display panel 10 may be flat. Accordingly, the display device may bemade thinner, and therefore have a tidy look.

Referring to FIG. 40, in the display device according to an embodimentof the present invention, the magnets 64 may be positioned on the firstmodule cover section 15 a as well as on the third module cover section15 c. However, the magnets 64 are not limited to such a configuration,but may be positioned in recesses provided in the first module coversection 15 a.

In this case, the module cover 15 and the display panel 10 may be heldtogether more firmly, compared to when the magnets 64 are positionedonly on the third module cover section 15 c. Accordingly, the displaypanel 10 and the module cover 15 may be kept from being easily detachedfrom each other even when external force is applied to them.

Referring to FIG. 41, in the display device according to an embodimentof the present invention, the top bar 75 and the module cover 15 may beattached, for example, with at least one screw.

The top bar 75 may be attached to the fourth module cover section 15 dthrough first holes 331. The fourth module cover section 15 d may coverthe back of the top bar 75. Although not shown, the display panel 10 aswell may be attached through the first holes 331.

The top bar 75 may be attached to the first module cover section 15 athrough second holes 333. As explained with reference to FIG. 10, a partwhich has a different thickness from the other part of the apron in theuppermost part of the first module cover section 15 a, may be insertedinto a recess in the top bar 75. The second holes 333 may be positionedlower than the first holes 331. The first module cover section 15 a andthe third module cover section 15 c may be attached to the top bar 75through different types of holes. Accordingly, the module cover 15 andthe top bar 75 may be held together more firmly.

The first module cover section 15 a and the third module cover section15 c may be attached to the second module cover section 15 b in therear, through third and fourth holes 335 and 337. The first module coversection 15 a may be attached to the second module cover section 15 bthrough the third holes 335 in the respective aprons, and the thirdmodule cover section 15 c may be attached to the second module coversection 15 b through the fourth holes 337 in the respective aprons.

Since the respective aprons are attached to the second module coversection 15 b through the third and fourth holes 335 and 337, the firstand third module cover sections 15 a and 15 c and the second modulecover section 15 b may be wound easily while being held together.

Referring to FIG. 42, the top bar 75 may include a first protrusion 75 aprotruding downward in the center and second protrusions 75 b protrudingdownward on both sides. The first protrusion 75 a may be a portion inwhich the first module cover section 15 a is inserted, and the secondprotrusions 75 b may be portions connecting to the supports 73. The topbar 75 may not be wound because it does not comprise of multiple partslike the aprons on the module cover 15. Thus, the first protrusion 75 aand the second protrusions 75 b may not be wound either.

Accordingly, flat regions FR of the first and third module coversections 15 a and 15 c, which correspond to the first and secondprotrusions 75 a and 75 b of the top bar 75, and the fourth module coversection 15 d, which corresponds to other parts of the top bar 75, mayremain flat in the first state, without being wound around the apronroller 141. For example, the uppermost apron may be positioned in theflat regions FR of the first and third module cover sections 15 a and 15c.

Referring to FIG. 43, in the display device according to an embodimentof the present invention, each hinge 152 may include a body 152 a and anattachment part 152 b.

As previously described, the body 152 a may be a part that connects theupper link 73 a and the lower link 73 b to allow the upper link 73 aband the lower link 73 b to rotate on the second module cover section 15b.

The attachment part 152 b may be connected to the body 152 a. Theattachment part 152 b may protrude toward the first module cover section15 a from the body 152 a. In the first state, the attachment parts 152 bmay not come into contact with the first module cover section 15 a.Accordingly, the supports 73 may rotate freely without being obstructedby the attachment parts 152 b.

During the transition from the first state to the second state,trajectories 367 may be formed on the second module cover section 15 bin which the attachment parts 152 b move. The trajectories 367 may beformed on the side of the second module cover section 15 b facing thedisplay panel. The trajectories 367 may include a magnetic material. Oneof the trajectories 367 may be shaped like the circumference of aquadrant that extends from the center of the left side of the secondmodule cover section 15 b along the second direction to the top adjacentto the first module cover section 15 a along the second direction. Theother trajectory 367 may be shaped like the circumference of a quadrantthat extends from the center of the right side of the second modulecover section 15 b along the second direction to the top adjacent to thefirst module cover section 15 a.

The attachment parts 152 b each may include a magnetic material on theside facing the second module cover section 15 b. The attachment parts152 b may include a material whose polarity is opposite to that of thetrajectories 167. The attachment parts 152 b may move along thetrajectories 167 during the transition from the second state to thefirst state.

Since the attachment parts 152 b and the trajectories 167 includemagnetic material, the hinges 152 may move while attached to the secondmodule cover section 15 b. Accordingly, the hinges 152 may not protrudeforward in any circumstances, thus allowing the display panel to remainflat. Also, the trajectories 367 may guide the movement of the hinges152. Accordingly, the protection of the display device during statetransitions can be improved.

While the aforementioned drawings are illustrated in relation to astructure of a display device in which the display portion is rolled upfrom inside the housing, the present invention is not limited to thisstructure but may be applicable to a structure of a display device inwhich the display portion is rolled down from inside the housing.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the scope of the principles of thisdisclosure. More particularly, various variations and modifications arepossible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

1-20. (canceled)
 21. A display device comprising: a housing; a rollerpositioned in the housing and elongated; a display portion configured towind around the roller when the roller is configured to rotate in afirst direction, the display portion configured to unwind from theroller when the roller is configured to rotate in a second direction; afoldable link including a lower link pivotally connected to the housingand an upper link pivotally connected to an upper part of the displayportion; a motor positioned in the housing and configured to pivot thelower link; and a driver positioned in the housing and configured torotate the roller in the first direction.
 22. The display device ofclaim 21, wherein the driver configures to rotate the roller in thefirst direction when the motor configures to pivot the lower link in athird direction of the lower link.
 23. The display device of claim 21,wherein the roller is configured to rotate in the second direction whenthe motor configures to pivot the lower link in a fourth direction ofthe lower link.
 24. The display device of claim 23, wherein the driverincludes a belt configured to rotate the roller in the first directionwhen the motor configures to pivot the lower link in the third directionof the lower link.
 25. The display device of claim 24, wherein the beltis configured to wind around the roller when the motor configures topivot the lower link in the fourth direction of the lower link.
 26. Thedisplay device of claim 24, wherein the belt is configured to unwindfrom the roller when the motor configures to pivot the lower link in thethird direction of the lower link.
 27. The display device of claim 24,wherein the belt includes an elastic body.
 28. The display device ofclaim 24, wherein the roller is a first roller and the driver furtherincludes a second roller positioned in the housing and opposite to thefirst roller, and wherein the belt links the first roller and the secondroller.
 29. The display device of claim 28, wherein the first roller isconfigured to rotate in the first direction when the belt configures totransfer power from the second roller to the first roller.
 30. Thedisplay device of claim 28, further comprising a mount installed in thehousing, wherein the first roller and the second roller are rotatablyconnected to the mount.
 31. The display device of claim 23, wherein thedriver includes a rolled constant spring configured to rotate in thehousing and spaced apart from the roller, and wherein a part of therolled constant spring is extended and wound around the roller.
 32. Thedisplay device of claim 31, wherein the roller is configured to rotatein the first direction when the motor configures to pivot the lower linkin the third direction of the lower link and a restoring force of theconstant spring is transmitted to the roller.
 33. The display device ofclaim 31, wherein a rotational direction of the roller and a rotationaldirection of the rolled constant spring are identical.
 34. The displaydevice of claim 31, wherein a rotational direction of the roller and arotational direction of the rolled constant spring are opposite to eachother.
 35. The display device of claim 31, wherein a torque of theroller is larger than a torque of the rolled constant spring when themotor configures to pivot the lower link in the fourth direction of thelower link.
 36. The display device of claim 31, further comprising amount installed in the housing, wherein the roller and the rolledconstant spring are rotatably connected to the mount.
 37. The displaydevice of claim 23, wherein the upper link configures to stand when thelower link is configured to pivot in the fourth direction of the lowerlink, and wherein the upper link configures to lie down when the lowerlink is configured to pivot in the third direction of the lower link.38. The display device of claim 22, further comprising: a fasteningportion configures to linearly move to a length direction of the roller;a spring pushing one side of the fastening portion; and a transmissionportion having one side pivotally connected to the lower link and theother side pivotally connected to the other side of the fasteningportion.
 39. The display device of claim 38, wherein the transmissionportion configures to stand when the lower link configures to pivot inthe fourth direction of the lower link, and wherein the transmissionportion configures to lie down when the lower link configures to pivotin the third direction of the link.
 40. The display device of claim 21,wherein the display portion includes a display panel and a module covercovers a rear surface of the display panel.